This article, although superficially, trying to establish a approch between Communicational Theory of Law and Constructivism Logical-Semantic, two lines of legal thinking which have grown in number of followers. Among the various points of analysis, the proposal presented emphasizes the types of legal rules of each theory and for this, use the formula of norm-matrix tributary incidence created by Paulo de Barros Carvalho, brazilian teacher who has many years devoted to tax studies. So, seeking to make the necessary dialogue, we chose the study of the criteria of this important rule, what we believe to be a starting point for future developments.